Slit Edge Burr Causing Feed Damage – Causes, Inspection, Repair & Prevention Guide for Roll Forming Machines

Slit Edge Burr Causing Feed Damage

Roll Forming Machine Troubleshooting & Repair Guide

Slit edge burrs are a common material quality problem that can create serious feeding and equipment issues in roll forming production lines. When steel coil is slit from a wider master coil, the cutting process may leave a sharp raised edge known as a burr.

If slit edge burrs are present when the strip enters a roll forming machine, they can cause several operational problems including:

• Damage to entry guide rollers
• Scratching of roll forming tooling
• Strip feeding instability
• Increased roller wear
• Surface defects on finished panels
• Safety hazards for operators

For manufacturers producing metal roofing panels, cladding sheets, structural decking, purlins, trims, and other roll formed products, managing slit edge burrs is critical to maintaining both product quality and machine longevity.

This guide explains the causes of slit edge burrs, inspection procedures, repair techniques, and preventative measures used by experienced roll forming technicians.

Causes of Wear or Failure

Slit edge burrs typically originate during the coil slitting process at steel service centers or mills.

Dull Slitting Knives

One of the most common causes of burr formation is worn or dull slitting knives.

When knives lose sharpness:

• The steel is torn rather than cleanly cut
• Burrs form along the slit edge

Incorrect Knife Clearance

Proper clearance between the upper and lower slitting knives is essential.

If the clearance is too large or too small, the cut quality may deteriorate and produce burrs.

Improper Slitting Setup

Incorrect slitting pressure or alignment may cause uneven cuts.

This increases burr formation along the strip edges.

Material Hardness

Harder steels such as high-strength steel grades are more difficult to slit cleanly.

This can increase the likelihood of burr formation.

Poor Maintenance of Slitting Equipment

Slitting lines that are not properly maintained may produce inconsistent edge quality.

Regular inspection of knife condition and alignment is necessary.

Why It Happened and What Caused It

From a mechanical perspective, burrs occur when the steel strip is sheared rather than cleanly cut.

During the slitting process:

1. The upper and lower knives compress the strip.
2. A fracture occurs through the material thickness.
3. If the knives are not sharp or aligned correctly, a raised edge remains.

When burrs enter the roll forming line, they create several problems:

• Burrs may scrape against guide rollers
• Burrs may damage roller surfaces
• Burrs may cause strip misalignment

Additionally, burrs may scratch protective coatings on painted or galvanized materials, affecting finished product appearance.

How to Inspect the Problem

Inspection Procedure

Detecting slit edge burrs before production helps prevent machine damage.

Step 1 – Visual Edge Inspection

Look closely at the slit edges of the strip.

Signs of burrs include:

• Raised sharp edges
• Rough or uneven cuts
• Visible metal fragments along the edge

Step 2 – Run a Gloved Hand Along the Edge

Carefully run a gloved hand along the strip edge.

If burrs are present, you will feel a sharp ridge.

Always use protective gloves to avoid injury.

Step 3 – Inspect Entry Guides

Check entry guide rollers for scratches or wear patterns.

These may indicate burr contact.

Step 4 – Examine Roller Surfaces

Inspect roll forming rollers for:

• Surface scratches
• Coating damage
• Wear marks along roller shoulders

Step 5 – Inspect Finished Product Edges

If burrs are entering the machine, finished products may show:

• Edge scratches
• Coating damage
• Rough panel edges

Step-by-Step Technician Guide – How to Fix

Several corrective actions can be used depending on the severity of the burr.

Method 1 – Deburr the Strip Edge

For minor burrs:

1. Use a deburring tool or abrasive device.
2. Smooth the strip edge before feeding it into the machine.

This removes the sharp ridge.

Method 2 – Trim the Strip Edge

If burrs are excessive:

1. Trim a small portion of the strip edge using a slitter or shear.
2. Ensure the remaining edge is smooth.

Method 3 – Adjust Entry Guides

Ensure entry guide rollers are properly aligned to prevent burrs from contacting machine components.

Method 4 – Reduce Production Speed

Running at lower speeds reduces the risk of burrs damaging rollers during feeding.

Method 5 – Reject Poor Quality Coil

If burrs are severe along the entire coil length, rejecting the material may be necessary.

Running severely burred material may damage expensive tooling.

Preventative Maintenance Tips

Preventing slit edge burr problems requires coordination with material suppliers and proper inspection procedures.

Work With Quality Slitting Service Centers

Reliable service centers maintain sharp knives and proper slitting setup.

Request Edge Quality Specifications

Material orders should specify acceptable slit edge conditions.

Inspect Incoming Coil Edges

Before loading coils, inspect strip edges for burrs.

Early detection prevents machine damage.

Maintain Entry Guide Rollers

Guide rollers should be inspected regularly for damage caused by burrs.

Train Operators on Edge Inspection

Operators should know how to identify burrs and take corrective action before production begins.

FAQ Section

What is a slit edge burr?

A slit edge burr is a sharp raised edge left on steel strip after the slitting process.

Why do burrs cause problems in roll forming?

Burrs can damage entry guides, rollers, and strip surfaces as the material feeds through the machine.

Can burrs affect finished product quality?

Yes. Burrs may scratch coatings or create rough panel edges.

How can burrs be removed?

Minor burrs can be removed using deburring tools or trimming the strip edge.

What causes burrs during slitting?

Common causes include dull slitting knives, incorrect knife clearance, and poor slitting alignment.

Should coils with severe burrs be rejected?

Yes. Severe burrs can damage roll forming equipment and should be addressed before production.

Machine Matcher Technical Support

If your roll forming production line is experiencing feeding problems, roller damage, or strip surface defects caused by poor material edge quality, Machine Matcher technical specialists can help diagnose and resolve the issue.

Support services include:

• Roll forming machine troubleshooting
• Strip feeding diagnostics
• Entry guide inspection
• Production line evaluation
• Remote technical assistance

Submit your issue through the Machine Matcher Technical Support Desk:

Include the following information:

• Machine type
• Coil width and thickness
• Photos of the strip edges
• Photos or videos of the feeding issue
• Profile drawing and production speed

Our technicians will review the information and provide detailed recommendations to restore efficient production.